CN103772330B - Method for recovery of furfural and acetic acid from furfural stripping steam condensate - Google Patents
Method for recovery of furfural and acetic acid from furfural stripping steam condensate Download PDFInfo
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- CN103772330B CN103772330B CN201210408429.5A CN201210408429A CN103772330B CN 103772330 B CN103772330 B CN 103772330B CN 201210408429 A CN201210408429 A CN 201210408429A CN 103772330 B CN103772330 B CN 103772330B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
- C07D307/02—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings
- C07D307/34—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members
- C07D307/38—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom not condensed with other rings having two or three double bonds between ring members or between ring members and non-ring members with substituted hydrocarbon radicals attached to ring carbon atoms
- C07D307/40—Radicals substituted by oxygen atoms
- C07D307/46—Doubly bound oxygen atoms, or two oxygen atoms singly bound to the same carbon atom
- C07D307/48—Furfural
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/48—Separation; Purification; Stabilisation; Use of additives by liquid-liquid treatment
Abstract
The invention relates to a method for recovery of furfural and acetic acid from a furfural stripping steam condensate, and the method is as follows: countercurrent contact of the furfural stripping steam condensate and an extractant is performed in an extraction tower to obtain an extraction phase containing the extractant, the furfural, the acetic acid and trace of water in a tower kettle and obtain an extraction residue phase being water containing trace of the furfural and the acetic acid at the tower top; the extraction phase enters into an extractant regeneration tower for separation to obtain the extractant and a small amount of the water at the tower top, and a tower top organic phase returns back to the extraction tower for cycle use after cooling, a water phase as wastewater is discharged, and a furfural and acetic acid mixture containing no water is obtained in the tower kettle; the furfural and the acetic acid mixture enters into a finished product tower for separation to obtain a furfural product with the purity of being greater than 99wt% in the tower kettle and obtain an acetic acid product with the purity of being greater than 99wt% at the tower top. The method can simultaneously recover the furfural and the acetic acid, the recovery rate is higher than 90%, the purity of products is higher than 99%, the extraction efficiency is high, and the unit energy consumption is less.
Description
Technical field
The invention belongs to Chemicals technical field of purification, particularly a kind of method adopting double solvents simultaneously extraction and recovery furfural and acetic acid from furfural aqueous solution.
Background technology
Furfural has another name called furtural, is a kind of important heterocyclic organic compound.Up to now, furfural can only be that raw material obtains with vegetable fibre, mainly corn cob, bagasse etc., is also several bio-based platform chemicals taking lignocellulose-like biomass as raw material large-scale commercial and produce few in number at present simultaneously.
Traditional furfural production is rich in the straw of hemicellulose for raw material (such as corn cob, bagasse etc.), first half fiber under the effect of sulfuric acid catalyst in lignocellulose is hydrolyzed and mainly generates pentose, and pentose generates furfural through dehydration cyclization again.Because furfural especially easily side reaction occurs under its reaction conditions, the industrial mode often through passing into water vapor continuously in reactor takes reaction system out of to improve furaldehyde yield the furfural that reaction generates.Under the condition that furfural generates; ethanoyl on hemicellulose molecule side chain is also easily oxidized to come off thus generates acetic acid; therefore the stripped vapor passing into reactor can take reaction system out of furfural and byproduct acetic acid simultaneously, that is both also contains acetic acid containing furfural in furfural stripped vapor phlegma.
In furfural stripped vapor phlegma, furfural content is about 5wt% ~ 8wt%, and acetate concentration is about 1wt% ~ 2wt %.Because furfural and water form azeotrope, in order to obtain finished product furfural, current industrial employing five tower process for refining extracts furfural product from furfural stripped vapor phlegma, and acetic acid remains in the furfural waste-water being formed in water and be rich in acetic acid.Due to organism such as the furfurals containing acetic acid and trace in furfural waste-water, COD value is up to more than 35000, if directly discharge, environmental pollution is serious, is also the waste of resource simultaneously.
Along with the further investigation of liquid-liquid extraction techniques, find to adopt liquid-liquid extraction method from furfural aqueous solution, to extract energy consumption needed for furfural significantly lower than traditional five tower process for refining, the method is considered to a kind of furfural most with industrial prospect and extracts new technology.Recent year scholar develops again the technology adopting liquid-liquid extraction techniques to reclaim acetic acid in furfural waste-water, both can recovery of acetic acid, making again the COD value of furfural waste-water decline to a great extent, creating condition for processing furfural waste-water further.
Chinese patent CN 101172941 A discloses a kind of method from reclaiming acetic acid dilute acetic acid aqueous solution, and this patent adopts the composition of mixed amine, alphanol and kerosene as composite extractant; Chinese patent CN 102267889 A discloses a kind of with the method for the mixture of isobutyl acetate, n-butyl acetate, Iso Butyl Acetate and the correspondent alcohol recovery of acetic acid that is extraction agent from dilute acetic acid aqueous solution; It take octanol as the method for extraction agent recovery of acetic acid from dilute acetic acid aqueous solution that Chinese patent CN 1626494 A discloses a kind of.Boil alcohol as extraction agent using height in foregoing invention or directly, boil the important component of alcohol as composite extractant to improve the selectivity of Dichlorodiphenyl Acetate using height, but the fatal defects that above-mentioned solvent exists be alcohols easily and acetic acid generation esterification cause the loss of alcohols serious, and greatly reducing the effect of extracting of extraction agent, this makes this technology to apply in the industry.Article that Huang Feng, Zhang Yulin deliver at it method of recovery of acetic acid " from the acid-bearing wastewater " research shows the selectivity of the selectivity of ethyl acetate Dichlorodiphenyl Acetate much larger than the double solvents Dichlorodiphenyl Acetate of the compound compositions such as mixed amine, alphanol and kerosene.Although ethyl acetate has larger partition ratio, the solubleness of ethyl acetate in water is too large, causes extraction agent to lose serious, makes it cannot as the extraction agent of acetic acid recovery process.
Summary of the invention
For the deficiencies in the prior art, the invention provides a kind of double solvents that adopts is the method for extraction agent extraction and recovery furfural and acetic acid from furfural stripped vapor phlegma, comprises the steps:
(1) furfural stripped vapor phlegma and extraction agent counter current contact in extraction tower, tower reactor obtains the extraction phase containing extraction agent, furfural, acetic acid and minor amount of water, and the extracting phase that tower top obtains is the water containing micro-furfural and acetate in minute;
(2) extraction phase in step (1) enters extractant regeneration tower and is separated, tower top phase splitter obtains the mixture of extraction agent and the water regenerated, the extraction agent of regeneration returns extraction tower and recycles after cooling, and water is arranged outward, and tower reactor obtains water-free furfural and vinegar stock;
(3) tower reactor gained furfural enters finishing column with the mixture of acetic acid and is separated in step (2), and tower reactor obtains finished product furfural, and its purity is greater than 99wt%, and tower top obtains finished product acetic acid, and its purity is greater than 99wt%;
In the inventive method, in step (1), extraction tower extraction agent used is composite extractant, and described extraction agent is the hydrochloric ether that benzene, ethyl acetate and boiling point are less than acetic acid boiling point, wherein, benzene accounts for 10wt% ~ 60wt%, and ethyl acetate accounts for 10wt% ~ 30wt%, and hydrochloric ether accounts for 10wt% ~ 60wt%.Preferably, benzene accounts for 20wt% ~ 40wt%, and ethyl acetate accounts for 15wt% ~ 25wt%, and hydrochloric ether accounts for 20wt% ~ 40wt%.
In the inventive method, described hydrochloric ether can be specifically the mixture of one or more the above-mentioned hydrochloric ethers in trichloromethane, trieline, 1，1，1-trichloroethane, vinyl trichloride.
In the inventive method, composite extractant also plays the effect of entrainer simultaneously, and in extractant regeneration tower, extraction agent and water form azeotrope and the moisture in furfural and vinegar stock is taken to tower top.
In the inventive method, extraction tower used is Pulsed Packed Extraction Column, wherein inner-tower filling material height is equivalent to 5 ~ 20 blocks of theoretical trays, the operational condition of extraction tower is: extraction agent and furfural stripped vapor phlegma input material volume ratio are 3 ~ 6:1, extraction temperature is 30 ~ 50 DEG C, pressure is normal pressure, and pulse-repetition is 0.01 ~ 10s
-1, pulsating pressure is 100 ~ 500 kPa.
In the inventive method, extractant regeneration tower is packing tower, and wherein inner-tower filling material height is equivalent to 5 ~ 30 blocks of theoretical trays, and working pressure is normal pressure, and reflux ratio is 1 ~ 5, tower top temperature 60 ~ 100 DEG C, bottom temperature 140 ~ 180 DEG C.In the extraction agent of regeneration, furfural and acetate concentration sum are less than 0.01%.
In the inventive method, finishing column is packing tower, and wherein inner-tower filling material height is equivalent to 5 ~ 30 blocks of theoretical trays, and working pressure is 20 ~ 90 kPa, and reflux ratio is 1 ~ 5, tower top temperature 60 ~ 90 DEG C, bottom temperature 100 ~ 140 DEG C.Tower reactor furfural product purity is greater than 99% (wt), and tower top acetate products purity is greater than 99% (wt).
The inventive method tool has the following advantages:
(1) in the inventive method, have employed double solvents as extraction agent, wherein, ethyl acetate Dichlorodiphenyl Acetate and furfural all have very high selectivity, benzene and hydrochloric ether all have very high selectivity to furfural, benzene and hydrochloric ether are water-soluble hardly and have very high selectivity to ethyl acetate, and ethyl acetate can be made water-soluble hardly, solve ethyl acetate because of in water solubleness large and can not as the problem of extraction agent; Hydrochloric ether can also play the effect regulating composite extractant density and viscosity simultaneously; This composite extractant all has very high selectivity to furfural and acetic acid, furfural and acetic acid can be reclaimed through single extraction operation simultaneously, the furfural rate of recovery is greater than 92%, and recovery rate is greater than 95%, and extracting phase can be used as oiler feed and also can directly discharge after simple process again.
(2) the inventive method, in the composite extractant adopted, benzene and ethyl acetate all can form azeotrope with water, therefore composite extractant can also play the entrainer effect of dehydration, this makes dehydration of the present invention need not add other entrainer, so present invention process flow process is simple, and be separated the furfural that obtains and acetate products purity high, and furfural waste-water intractability is reduced greatly, the efficiency extracting furfural and acetic acid from furfural stripped vapor phlegma is improved greatly.
(3), in the inventive method, described extraction agent wide material sources, stable chemical nature, technological process are simple, and product purity is high, and furfural and acetate products purity all can reach more than 99%.
Accompanying drawing explanation
Fig. 1 is present invention process schematic flow sheet.
Embodiment
Composition graphs 1, the inventive method technical process is further illustrated, furfural stripped vapor phlegma 1 and extraction agent 2 enter Pulsed Packed Extraction Column 5 from tower reactor and tower top respectively, tower reactor has pulse of air to blast, furfural stripped vapor phlegma 1 and extraction agent 2 counter current contact in Pulsed Packed Extraction Column 5, after extracting and separating, extracting phase 6 and extraction phase 4 is obtained respectively at tower top and tower reactor, described extracting phase 6 can do oiler feed or directly discharge after simple process, extraction phase 4 enters extractant regeneration tower 7 and carries out regeneration separation, the extraction agent of regeneration and a small amount of water is obtained at tower top, aqueous phase is directly as discharge of wastewater, extraction agent 9 returns Pulsed Packed Extraction Column 5 and recycles after water cooler 3 cools, regenerator column 7 tower reactor obtains water-free furfural and vinegar stock 10, furfural and vinegar stock 10 enter finishing column 11 and are separated, tower top obtains finished product acetic acid 12, tower reactor obtains finished product furfural 13.
Below by specific embodiment, the invention will be further described, but the scope of the invention is not limited to scope described in embodiment.
Embodiment 1:
In furfural stripped vapor phlegma, furfural content and acetate concentration are respectively 5.2% (wt) and 1.6% (wt).
Extraction agent is benzene, ethyl acetate, trieline mixed solvent, and wherein, benzene accounts for 40wt%, and ethyl acetate accounts for 20wt%, and trieline accounts for 40wt%.
The in-built silk filling corrugated wire gauze packing of Pulsed Packed Extraction Column, virtual height 5 meters, is equivalent to 10 blocks of theoretical trays, and extraction agent and furfural stripped vapor phlegma charge ratio are 3:1, and extraction temperature 31 DEG C, pulse-repetition is 2s
-1, after stable operation, the temperature of extraction phase and extracting phase is respectively 36 DEG C and 40 DEG C.
The in-built silk filling corrugated wire gauze packing of extractant regeneration tower, virtual height 4 meters, is equivalent to 28 blocks of theoretical trays, feed entrance point is being equivalent to the 10th piece of column plate place, and reflux ratio is 2, working pressure normal pressure, after stable operation, the temperature of tower top and tower reactor is respectively 72 DEG C and 146 DEG C.
The in-built silk filling corrugated wire gauze packing of finishing column tower, virtual height 4 meters, is equivalent to 28 blocks of theoretical trays, and feed entrance point is at the 15th block of column plate, and reflux ratio is 2, and working pressure is 30Kpa, and after stable operation, the temperature of tower top and tower reactor is respectively 82.5 DEG C and 125.8 DEG C.
Specific experiment the results are shown in Table 1.
Embodiment 2:
Substantially the same manner as Example 1, but extraction agent and furfural stripped vapor phlegma charge ratio are 1:1.
Embodiment 3:
Substantially the same manner as Example 1, but extraction agent and furfural stripped vapor phlegma charge ratio are 5:1.
Embodiment 4:
Substantially the same manner as Example 1, but composite extractant composition becomes: benzene, ethyl acetate, trieline mass ratio 3:1:1.
Embodiment 5:
Substantially the same manner as Example 1, but composite extractant composition becomes: benzene, ethyl acetate, trieline mass ratio 1:1:3.
Embodiment 6:
Substantially the same manner as Example 1, but composite extractant composition becomes: benzene, ethyl acetate, trieline mass ratio 1:0:1.
Embodiment 7:
Substantially the same manner as Example 1, but composite extractant composition becomes: benzene, ethyl acetate, trieline mass ratio 0:1:1.
Embodiment 8:
Substantially the same manner as Example 1, but composite extractant composition becomes: benzene, ethyl acetate, trieline mass ratio 1:1:0.
Embodiment 9:
Substantially the same manner as Example 1, but extraction tower service temperature becomes 45 DEG C.
Embodiment 10:
Substantially the same manner as Example 1, but extraction tower service temperature becomes 55 DEG C.
Embodiment 11:
Substantially the same manner as Example 1, but extraction tower pulse-repetition becomes 1s
-1.
Embodiment 12:
Substantially the same manner as Example 1, but extraction tower pulse-repetition becomes 3s
-1.
Table 1 embodiment result
| Embodiment | The furfural rate of recovery, % | Furfural purity, % | Recovery rate, % | Acetic acid purity, % |
| 1 | 88.8 | 99.5 | 91.1 | 99.5 |
| 2 | 84.0 | 99.5 | 86.3 | 99.3 |
| 3 | 92.5 | 99.6 | 95.5 | 99.6 |
| 4 | 83.5 | 99.6 | 85.5 | 99.6 |
| 5 | 93.5 | 99.6 | 86.5 | 99.6 |
| 6 | 90.0 | 99.0 | 23.4 | 97.2 |
| 7 | 82.1 | 99.1 | 90.9 | 99.5 |
| 8 | 88.3 | 99.5 | 86.0 | 99.6 |
| 9 | 84.9 | 99.2 | 83.6 | 99.3 |
| 10 | 79.5 | 99.3 | 75.5 | 99.2 |
| 11 | 84.8 | 99.2 | 85.2 | 99.4 |
| 12 | 90.1 | 99.4 | 91.0 | 99.5 |
Claims (6)
1. from furfural stripped vapor phlegma, reclaim a method for furfural and acetic acid, comprise the steps:
(1) furfural stripped vapor phlegma and extraction agent counter current contact in extraction tower, tower reactor obtains the extraction phase containing extraction agent, furfural, acetic acid and minor amount of water, and the extracting phase that tower top obtains is the water containing micro-furfural and acetate in minute;
(2) extraction phase in step (1) enters extractant regeneration tower and is separated, tower top phase splitter obtains the mixture of extraction agent and the water regenerated, the extraction agent of regeneration returns extraction tower and recycles after cooling, and water is arranged outward, and tower reactor obtains water-free furfural and vinegar stock;
(3) tower reactor gained furfural enters finishing column with the mixture of acetic acid and is separated in step (2), and after separation, tower reactor obtains finished product furfural, and its purity is greater than 99wt%, and tower top obtains finished product acetic acid, and its purity is greater than 99wt%;
Wherein, in step (1), extraction tower extraction agent used is composite extractant, comprise the hydrochloric ether that benzene, ethyl acetate and boiling point are less than acetic acid boiling point, wherein, described hydrochloric ether is trichloromethane, trieline, 1，1，1-trichloroethane, 1, the mixture of one or more in 1,2-trichloroethane.
2. in accordance with the method for claim 1, it is characterized in that: in described extraction agent, benzene accounts for 10wt% ~ 60wt%, and ethyl acetate accounts for 10wt% ~ 30wt%, and hydrochloric ether accounts for 10wt% ~ 60wt%.
3. in accordance with the method for claim 1, it is characterized in that: in described extraction agent, benzene accounts for 20 ~ 40wt%, and ethyl acetate accounts for 15 ~ 25wt%, and hydrochloric ether accounts for 20 ~ 40wt%.
4. in accordance with the method for claim 1, it is characterized in that: extraction tower is Pulsed Packed Extraction Column, wherein inner-tower filling material height is equivalent to 5 ~ 20 blocks of theoretical trays, the operational condition of extraction tower is: extraction temperature is 30 ~ 50 DEG C, pressure is normal pressure, extraction agent and furfural stripped vapor phlegma input material volume ratio are 3 ~ 6:1, and pulse-repetition is 0.01 ~ 10s
-1, pulsating pressure is 100 ~ 500kPa.
5. in accordance with the method for claim 1, it is characterized in that: extractant regeneration tower is packing tower, wherein inner-tower filling material height is equivalent to 5 ~ 30 blocks of theoretical trays, working pressure is normal pressure, reflux ratio is 1 ~ 5, tower top temperature 60 ~ 100 DEG C, bottom temperature 140 ~ 220 DEG C.
6. in accordance with the method for claim 1, it is characterized in that: finishing column is packing tower, wherein inner-tower filling material height is equivalent to 5 ~ 30 blocks of theoretical trays, working pressure is 20 ~ 90 kPa, reflux ratio is 1 ~ 5, tower top temperature 60 ~ 90 DEG C, bottom temperature 100 ~ 140 DEG C.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210408429.5A CN103772330B (en) | 2012-10-24 | 2012-10-24 | Method for recovery of furfural and acetic acid from furfural stripping steam condensate |
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|---|---|---|---|
| CN201210408429.5A CN103772330B (en) | 2012-10-24 | 2012-10-24 | Method for recovery of furfural and acetic acid from furfural stripping steam condensate |
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| CN103772330A CN103772330A (en) | 2014-05-07 |
| CN103772330B true CN103772330B (en) | 2015-06-17 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109081821B (en) * | 2018-10-22 | 2023-09-15 | 江阴市大洋固废处置利用有限公司 | Furfural recovery device and recovery method for condensate liquid in ceramic production |
| CN112876435B (en) * | 2021-03-02 | 2022-01-04 | 安徽金轩科技有限公司 | Refining method of furfural |
| CN113578272B (en) * | 2021-07-22 | 2023-04-07 | 太原理工大学 | Ordered ZIF-8-based mesoporous carbon material with large aperture and ultra-large pore volume as well as preparation method and application thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB774809A (en) * | 1953-07-29 | 1957-05-15 | Oronzio De Nora Impianti | A continuous process for the production of furfural and acetic acid from pentosan-containing material |
| US4729818A (en) * | 1987-04-16 | 1988-03-08 | Lloyd Berg | Dehydration of acetic acid by extractive distillation |
| CN101172941A (en) * | 2006-11-02 | 2008-05-07 | 中国石油化工股份有限公司 | Method for recycling acetic acid in dilute acetic acid |
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2012
- 2012-10-24 CN CN201210408429.5A patent/CN103772330B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB774809A (en) * | 1953-07-29 | 1957-05-15 | Oronzio De Nora Impianti | A continuous process for the production of furfural and acetic acid from pentosan-containing material |
| US4729818A (en) * | 1987-04-16 | 1988-03-08 | Lloyd Berg | Dehydration of acetic acid by extractive distillation |
| CN101172941A (en) * | 2006-11-02 | 2008-05-07 | 中国石油化工股份有限公司 | Method for recycling acetic acid in dilute acetic acid |
Non-Patent Citations (1)
| Title |
|---|
| 糠醛废水中的醋酸回收工艺;张晓辉等;《化学工程与工艺》;20061231;第23卷(第2期);142-146 * |
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